POS1261 DIAGNOSTIC ACCURACY OF LUNG ULTRASOUND FOR DETECTING INTERSTITIAL LUNG DISEASE AMONG PATIENTS WITH SYSTEMIC SCLEROSIS: A COMPARATIVE STUDY OF TWO SCANNING PROTOCOLS
Authors: F. Carranza-Enriquez, C. Soto, C. Pineda, T. S. Rodriguez-Reyne, A. Angeles-Acuna, S. Y. Solorzano Flores, A. Vazquez Ortega, I. J. Vazquez Romero, M. Mejia
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Lung ultrasound (LUS) has proven useful to detect interstitial lung disease (ILD) among patients with systemic sclerosis (SSc) when compared to high-resolution computerized tomography (HRCT) as the gold standard; owing to its accessibility and innocuity it confers several advantages over the latter, which turns it into a potential valuable tool in clinical practice. Nevertheless, a key drawback is the lack of a standardized methodology to perform LUS. <h3>Objectives</h3> To evaluate diagnostic accuracy of LUS for ILD by comparing the systematic evaluation of 14 intercostal spaces (ICS) against 12 postero-basal ICS. <h3>Methods</h3> Patients with SSc were included according to the 2013 ACR/EULAR classification criteria of the Rheumatology clinic of the National Institute of Medical Sciences and Nutrition, reference hospital in Mexico City. Demographic, clinical, serological, and imaging variables were collected, followed by LUS assessment with the simultaneous scanning of 14 predetermined ICS and 12 postero-basal ICS. "B" lines (BL) and pleural abnormalities (PA) were documented for each ICS. HRCT was performed with a maximum 3 month-interval from the time of recruitment (before or after). Descriptive statistics for categorical and continuous variables was used. A bivariate analysis was undertaken to discriminate factors associated with the presence of ILD. A Pearson correlation test was carried out to compare findings between LUS and HRCT. Diagnostic accuracy was assessed through elaboration of ROC curves. <h3>Results</h3> We included 73 patients, with a median age of 54.5±15.1 years and 96.1% were women. Prevalence of ILD was 43.6%. Relevant baseline characteristics are shown in Table 1. Acknowledged risk factors for ILD were pulmonary hypertension (OR 6.27, CI 95% 1.75-22.4, p=0.005) and diffuse SSc (OR 6.17, CI 95% 1.92-19.76, p=0.002). The AUC were 0.87 (95% CI, 0.78-0.96), 0.94 (95% CI, 0.88-1.00) and 0.84 (95% CI, 0.74-0.94) for the evaluation of the number of BL in 14 ICS, in 12 ICS and the number of ICS with PA (22 EIC), respectively. ROC curves are represented in Image 1. <h3>Conclusion</h3> Our study confirms the robustness of LUS as a tool for the detection of ILD through the quantification of BL and PA when using any of two different scanning protocols (14 and 12 ICS). However, more studies are required to elucidate the added value of pleural abnormalities identification for the diagnosis of ILD by LUS. <h3>References</h3> [1]Vicente-Rabaneda EF, Bong DA, Castañeda S. Use of ultrasound to diagnose and monitor interstitial lung disease in rheumatic diseases. Clin Rheumatol [Internet]. 2021;40(9):3547–64. [2]Ruaro B, Baratella E, Confalonieri P, et al. High-resolution computed tomography and lung ultrasound in patients with systemic sclerosis: Which one to choose? Diagnostics. 2021;11(12):1–12. <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> None Declared.